ORIGINAL: Greg / MO
gingus, I bought mine from 3Rivers Archery, and probably bought it six months prior to asssembling my cresting machine... so that puts it about two years ago, since I orginally wrote this thread a year and a half ago?
I ran a quick search for you and found that they offer this one now... looks like it's changed somewhat in shape and appearance. Hopefully, it will still work:
http://www.3riversarchery.com/Product.asp?c=2&s=8&p=27&i=4139
You may also want to try to contact Bohning directly and tell them you need a replacement chuck for one of their older-style machines.
Thats the same chuck that I have and I ordered mine from King Archery (I believe). It works just as good as anything else I'd assume.